Greetings!

Recently I had a few problems with a few sites I just start to handle (all on same IP):
www[dot]pmoz[dot]org
www[dot]pro-board[dot]com
www[dot]jdhealthcare[dot]com
Recently they got de-indexed by MSN, for a reason that remains wierd to me. Even more a few other sites that linked to these ones (located on different IPs) received a penalty (drop in SERPS).

Do you have any idea why this happend - as far as I know the sites are legitim and no black hat seo is used.

Please let me know if you notice anything that may result in this MSN ban / penalty.

Thank you in advance.